Lucid Dreams and Saturn Skies

The little girl zombie from Night of the Living Dead - quite possibly the creepiest zombie in all zombie history.

I find myself writing about zombies on this blog pretty often.  And why not?  Zombies are not only a pop culture phenomenon, but they’ve also long been a facet of folklore.  Now the rotting shamblers are all but ubiquitous, popping up in everything from commercials to television shows to movies.  Some folks have even gone so far as to plan their survival strategy for a zombie apocalypse – its gotten to the point where I can’t tell if people are having fun with it or if they honestly believe that one day the dead will rise.

Which leads to the million dollar question – could there be a real-life pathogen that could reanimate dead flesh like in the movies?  In a word, no.  But could there be pathogen of some sort that could result in an outbreak rather like 28 Days Later, where the zombies weren’t technically dead?

I think the latter scenario is more plausible from a biological perspective.  After all, in that movie the zombies weren’t walking corpses, but rather people infected with a virus.  The virus in 28 Days Later was called Rage, and it spread to the human population via infected monkeys released by animal activists (darned British equivalent of PETA!).  It was transmissible by fluid exchange, typically by bites.  It resulted in profound behavioral changes; namely it changed the British population into a pack of rabid, man eating maniacs that craved the warm flesh of the uninfected.

To determine if there is any virus out there that could be a potential zombie pathogen, let’s use Rage as a model.  So, we are looking for a virus that results in behavioral changes in its victims, especially an increase in violent and erratic behavior.  Also, said virus would have to be transmissible from human to human via fluid transfer (i.e. via blood, saliva, or sexual fluids).   It would require a rapid onset of symptoms, to make treatment with vaccines nearly impossible, and it would be almost 100% fatal.

Such constraints really limit the pool of likely suspects.  Barring the evolution of some new virus (not a completely implausible scenario given how fast these things evolve), a virus as ancient as mankind is the only viable suspect: rabies.  We’ve discussed rabies’ folkloric influence here on LDSS before, but could the virus be responsible for bringing to life yet another movie monster?

A dog afflicted with late stage rabies, so called "dumb" paralytic rabies.

Let’s see how it measures up.  Rabies is transmissible via bodily fluids – it’s usually spread by bites from infected animals such as bats, dogs, racoons, skunks, or foxes, among many other vectors.  It infects the central nervous system, and on the onset of symptoms it results in changes in behavior – disorientation, aggression, anxiety, paranoia, delirium, hydrophobia, depression, and mania.  Also, rabies is deadly 99% of the time, if left untreated.

So far, it looks like rabies is a pretty good candidate for an apocalyptic zombie virus. But don’t go boarding up your windows just yet zombie survival fans, because there are some serious flaws that prevent the virus from being a viable real world substitute for Rage.

For one, rabies is not easily transmissible among humans.  Most humans who are infected with the virus only become so after being bitten by an infected animal, often a dog or a bat.  However, there are no documented cases that I can find where rabies has been transmitted from person to person.  It’s even difficult for transmission to occur from animal to animal – once the primary carrier has passed its viral load to a victim, the secondary victim often can’t pass the virus on to any other individuals.

Another check against rabies as a zombie virus is the fact that it has a long incubation period – anywhere from ten days to a year.  The length of time before the onset of symptoms varies depending on how far the viral load has to travel along the peripheral nervous system until it reaches the brain, at which point the classic rabies symptoms commence.  This slow incubation period allows for medical intervention with vaccines, which if administered quickly enough are usually effective in preventing death.

It’s looking like rabies is a pretty lousy candidate for an apocalyptic zombie pathogen at this point.  But for the zombiephobes out there who are sighing with relief right now, I wouldn’t be so hasty.  Viruses are funny little organisms (well, not technically – they aren’t even alive in any real sense so they aren’t actually organisms.)  They evolve very quickly, and they tend to do things that surprise us. 

Who knew the bringers of the apocalypse would be so cute?

For example, in the northern part of Arizona, skunks and foxes infected with rabies have been cropping up.  This isn’t unusual in and of itself, but the strain of rabies they’re infected with is quite odd.  This strain of rabies can be spread easily from skunk to skunk (or fox to fox) via casual interactions, not unlike the flu which so plagues human populations in winter months.  This new strain seems to be spreading far and wide amongst wild fox and skunk populations.

For the moment though, this doesn’t make the disease anymore transmissible to humans.  It could make the disease more likely to spread to pets, however, which could lead to humans catching secondary infections they’re bit by their infected pets.  Experts aren’t worried just yet that rabies will spread like wildfire, like the flu, among human populations. In part because the new strain hasn’t been found in humans yet, and also because despite its increased virulence, this strain of rabies virus has the same incubation time as regular old rabies.  So, vaccines are still an effective treatment should it jump the species barrier.

But you never know.  A rabies virus that spreads easily from person to person, and one that happens to mutate a faster incubation time could very well be a real world equivalent to a zombie virus.

However, I wouldn’t hold my breathe.  From everything I know of biology, zombies are only barely on this side of plausible.  So rest well, zombiephobes.  The walking dead will remain the stuff of nightmares, where they belong.

Andrew Kincaid writes horror, blogs, and watches way too many scary movies..  He’s making the world a stranger place, one story at a time.  Get in touch with him on Facebook and Twitter, and check out his debut horror anthology ON DARK PATHS, available on Kindle!